U.S. patent application number 14/995230 was filed with the patent office on 2017-07-20 for calculating an effective heat transfer coefficient of a device.
The applicant listed for this patent is Motorola Mobility LLC. Invention is credited to Alberto R. Cavallaro, Maninder Sehmbey.
Application Number | 20170205365 14/995230 |
Document ID | / |
Family ID | 59315175 |
Filed Date | 2017-07-20 |
United States Patent
Application |
20170205365 |
Kind Code |
A1 |
Cavallaro; Alberto R. ; et
al. |
July 20, 2017 |
CALCULATING AN EFFECTIVE HEAT TRANSFER COEFFICIENT OF A DEVICE
Abstract
A method, a system, and computer program product for calculating
an effective heat transfer coefficient of a device. The method
includes measuring: an internal temperature of the device, a first
temperature at a first location along a first resistive path of a
parallel resistive network and a second temperature at a second
location along a second resistive path of the parallel resistive
network. An ambient temperature of the environment and an effective
heat transfer coefficient of the device is then calculated based on
the internal temperature, the first temperature, the second
temperature, and resistive properties of the parallel resistive
network. The ambient temperature and the effective heat transfer
coefficient are provided to a thermal management component.
Inventors: |
Cavallaro; Alberto R.;
(Northbrook, IL) ; Sehmbey; Maninder; (Hoffman
Estates, IL) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Motorola Mobility LLC |
Chicago |
IL |
US |
|
|
Family ID: |
59315175 |
Appl. No.: |
14/995230 |
Filed: |
January 14, 2016 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
G01K 7/427 20130101;
G06F 1/206 20130101; G06F 9/30083 20130101; G05D 23/27 20130101;
G01K 17/00 20130101; G01K 7/16 20130101; G06F 9/4893 20130101; G01N
25/20 20130101; G01K 7/425 20130101 |
International
Class: |
G01N 25/20 20060101
G01N025/20 |
Claims
1. A method comprising: measuring an internal temperature at a
particular location within a device; measuring, via a first thermal
sensor, a first temperature at a first location along a first
resistive path of a parallel resistive network having a pair of
resistive paths, wherein the first resistive path physically
extends between the particular location and an ambient environment;
measuring, via a second thermal sensor, a second temperature at a
second location along a second resistive path of the parallel
resistive network, wherein the second resistive path physically
extends between the particular location and the ambient
environment, and wherein the second resistive path is parallel to
the first resistive path; simultaneously calculating, based on the
internal temperature, the first temperature, the second
temperature, and pre-established resistive properties of the first
resistive path and the second resistive path: an ambient
temperature of the ambient environment and an effective heat
transfer coefficient of the device, wherein the effective heat
transfer coefficient represents a rate at which heat generated by
the device can be dissipated to the ambient environment in
proportion to the temperature difference between the device and the
ambient temperature; and providing the ambient temperature and the
effective heat transfer coefficient to a thermal management
component of the device.
2. The method of claim 1, wherein: the internal temperature at the
particular location is measured using an internal thermal sensor;
the particular location and the first thermal sensor are separated
by a first resistive material, and the first thermal sensor; the
particular location and the second thermal sensor are separated by
a second resistive material that is different from the first
resistive material; and the pre-established resistive properties
include a resistance of the first resistive material and a
resistance of the second resistive material.
3. The method of claim 2, wherein each of the internal thermal
sensor, the first thermal sensor, and the second thermal sensor is
tuned for a temperature range, and wherein any one thermal sensor
of the internal thermal sensor, the first thermal sensor, and the
second thermal sensor can be tuned for a particular temperature
range that corresponds to only that thermal sensor.
4. The method of claim 1, further comprising: determining, based on
the ambient temperature of the ambient environment and the
effective heat transfer coefficient of the device, whether a
current operating mode of the device is optimized for the ambient
environment; and in response to determining that the current
operating mode of the device is not optimized for the ambient
environment, applying at least one modification to the device that
corrects for at least one of (i) the effective heat transfer
coefficient of the device and (ii) at least one environmental heat
transfer condition in the ambient environment.
5. The method of claim 4, wherein the at least one modification
comprises a change from among an increase to and a decrease to at
least one of: a brightness level of a display, a maximum data rate
of at least one wireless radio, and an operating frequency of a
processor of the device.
6. The method of claim 4, wherein applying the at least one
modification to the device further comprises: calculating an
enhanced operating mode for the device, wherein the enhanced
operating mode establishes, for the ambient environment, at least
one maximum operating specification for at least one component of
the device that maintains a surface temperature of the device below
a pre-established maximum surface temperature threshold and
maintains the internal temperature below a pre-established maximum
internal operating temperature threshold; determining, based on the
calculated enhanced operating mode, whether at least one change
exists that can be applied to the at least one component that
changes a current operating mode of the device to the enhanced
operating mode, wherein the at least one modification includes the
at least one change, and wherein the at least one change indicates
that the current operating mode is not optimized for the ambient
environment; and in response to determining at least one change
exists that can be applied to the at least one component that
changes the current operating mode of the device to the enhanced
operating mode, applying the at least one change to the at least
one component.
7. The method of claim 4, further comprising: adjusting a
pre-determined maximum internal operating temperature threshold of
the device based on the ambient temperature of the ambient
environment and the effective heat transfer coefficient.
8. A device comprising: a thermal management component; an internal
thermal sensor at a particular location within the device and which
measures an internal temperature of the device; a parallel
resistive network that includes (i) a first resistive path
extending between the particular location and an ambient
environment of the device and comprising a first thermal sensor and
(ii) a second resistive path extending in parallel to the first
resistive path between the particular location and the ambient
environment and comprising a second thermal sensor; and a processor
communicatively coupled to the internal thermal sensor, the first
thermal sensor, and the second thermal sensor and which receives a
signal from the internal thermal sensor that identifies an internal
temperature of the device at the particular location, the processor
executing a thermal response firmware, wherein: the processor
receives, from the first thermal sensor, a first temperature at a
first location along the first resistive path; the processor
receives, from the second thermal sensor, a second temperature at a
second location along the second resistive path; the processor
simultaneously calculates, based on the internal temperature, the
first temperature, the second temperature, and pre-established
resistive properties of the first resistive path and the second
resistive path, an ambient temperature of the ambient environment
and an effective heat transfer coefficient of the device, wherein
the effective heat transfer coefficient represents a rate at which
heat generated by the device can be dissipated to the ambient
environment in proportion to the temperature difference between the
device and the ambient temperature; and the processor provides the
ambient temperature and the effective heat transfer coefficient to
the thermal management component to implement thermal management on
the device.
9. The device of claim 8, wherein: the particular location and the
first thermal sensor are separated by a first resistive material;
the particular location and the second thermal sensor are separated
by a second resistive material that is different from the first
resistive material; and the pre-established resistive properties
include a resistance of the first resistive material and a
resistance of the second resistive material.
10. The device of claim 9, wherein each of the internal thermal
sensor, the first thermal sensor, and the second thermal sensor is
tuned for a temperature range, and wherein any one thermal sensor
of the internal thermal sensor, the first thermal sensor, and the
second thermal sensor can be tuned for a particular temperature
range that corresponds to only that thermal sensor.
11. The device of claim 9, further comprising, in response to
receiving the effective heat transfer coefficient: the thermal
management component determines, based on the ambient temperature
of the ambient environment and the effective heat transfer
coefficient of the device, whether a current operating mode of the
device is optimized for the ambient environment; and in response to
determining that the current operating mode of the device is not
optimized for the ambient environment, the thermal management
component applies at least one modification to the device that
corrects for at least one of (i) the effective heat transfer
coefficient of the device and (ii) at least one environmental heat
transfer condition in the ambient environment.
12. The device of claim 11, wherein the at least one modification
comprises a change from among an increase to and a decrease to at
least one of: a brightness level of a display, a maximum data rate
of at least one wireless radio of the device, and an operating
frequency of the processor.
13. The device of claim 11, wherein in determining whether a
current operating mode of the device is optimized for the ambient
environment: the thermal management component calculates an
enhanced operating mode for the device, wherein the enhanced
operating mode establishes, for the ambient environment, at least
one maximum operating specification for at least one component of
the device that maintains a surface temperature of the device below
a pre-established maximum surface temperature threshold and
maintains the internal temperature below a pre-established maximum
internal operating temperature threshold; the thermal management
component determines, based on the enhanced operating mode, whether
at least one change exists that can be applied to the at least one
component that changes a current operating mode of the device to
the enhanced operating mode, wherein the at least one modification
includes the at least one change, and wherein the at least one
change indicates that the current operating mode is not optimized
for the ambient environment; and in response to determining at
least one change exists that can be applied to the at least one
component that changes the current operating mode of the device to
the enhanced operating mode, the thermal management component
applies the at least one change to the one component.
14. The device of claim 11, wherein: the thermal management
component adjusts a pre-determined maximum internal operating
temperature threshold of the device based on the ambient
temperature of the ambient environment and the effective heat
transfer coefficient.
15. A computer program product comprising: a computer readable
storage device; and program code on the computer readable storage
device that when executed within a processor associated with a
device, the program code enables the device to provide the
functionality of: receiving an input of an internal temperature
measured at a particular location within the device; receiving a
first temperature measured at a first location along a first
resistive path of a parallel resistive network having a pair of
resistive paths, wherein the first resistive path physically
extends between the particular location and an ambient environment;
receiving a second temperature measured at a second location along
a second resistive path of the parallel resistive network, wherein
the second resistive path physically extends between the particular
location and the ambient environment, and wherein the second
resistive path is parallel to the first resistive path;
simultaneously calculating, based on the internal temperature, the
first temperature, the second temperature, and pre-established
resistive properties of the first resistive path and the second
resistive path, an ambient temperature of the ambient environment
and an effective heat transfer coefficient of the device, wherein
the effective heat transfer coefficient represents a rate at which
heat generated by the device can be dissipated to the ambient
environment in proportion to the temperature difference between the
device and the ambient temperature; and providing the ambient
temperature and the effective heat transfer coefficient to a
thermal management component of the device.
16. The computer program product of claim 15, wherein: the internal
temperature at the particular location is measured using an
internal thermal sensor of the device; the first temperature at the
first location is measured using a first thermal sensor; the
particular location and the first thermal sensor are separated by a
first resistive material; the second temperature at the second
location is measured using a second thermal sensor; the particular
location and the second thermal sensor are separated by a second
resistive material that is different from the first resistive
material; and the pre-established resistive properties include a
resistance of the first resistive material and a resistance of the
second resistive material.
17. The computer program product of claim 16, wherein the program
code further comprising code that enables the device to provide the
functionality of: determining, based on the ambient temperature of
the ambient environment and the effective heat transfer coefficient
of the device, whether a current operating mode of the device is
optimized for the ambient environment; and in response to
determining that the current operating mode of the device is not
optimized for the ambient environment, applying at least one
modification to the device that corrects for at least one of (i)
the effective heat transfer coefficient of the device and (ii) at
least one environmental heat transfer condition in the ambient
environment.
18. The computer program product of claim 17, wherein the program
code for determining whether a current operating mode of the device
is optimized for the ambient environment further comprises code
that enables the device to provide the functionality of:
calculating an enhanced operating mode for the device, wherein the
enhanced operating mode establishes, for the ambient environment,
at least one maximum operating specification for at least one
component of the device that maintains a surface temperature of the
device below a pre-established surface temperature threshold and
maintains the internal temperature below a pre-established maximum
internal operating temperature threshold; determining, based on the
calculated enhanced operating mode, whether at least one change
exists that can be applied to the at least one component that
changes a current operating mode of the device to the enhanced
operating mode, wherein the at least one modification includes the
at least one change, and wherein the at least one change indicates
that the current operating mode is not optimized for the ambient
environment; and in response to determining at least one change
exists that can be applied to the at least one component that
changes the current operating mode of the device to the enhanced
operating mode, applying the at least one change to the at least
one component.
Description
BACKGROUND
[0001] 1. Technical Field
[0002] The present disclosure generally relates to electronic
devices and in particular to an improved method for calculating an
ambient temperature of an environment and an effective heat
transfer coefficient of an electronic device.
[0003] 2. Description of the Related Art
[0004] Due to numerous constraints, including size constraints,
many electronic devices, such as a mobile device, are deliberately
designed without active cooling solutions. Instead, these types of
electronic devices rely on passive cooling by the device and
continual monitoring of internal temperatures at key locations
throughout the device. These key locations can include at the
processor core, the memory, and/or various other locations
throughout a printed circuit board. Solutions currently exist to
maintain an internal temperature of a device below a threshold in
order to protect the device from harmful conditions, such as a
processor overheating. For example, an operating frequency of a
processor may be throttled down when the processor's temperature
reaches a threshold. However, these solutions regulate the
operation of a device based entirely on the device's internal
temperature and a pre-established acceptable internal temperature
range and do not account for environmental conditions of the
device. Additionally, current solutions are unable to measure an
ambient temperature of an environment by a same device that is
generating heat to the environment, and instead rely on receiving
ambient temperature data from a secondary device, such as a remote
computer or infrared thermometer.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] The description of the illustrative embodiments is to be
read in conjunction with the accompanying drawings, wherein:
[0006] FIG. 1 provides a block diagram representation of a device
within which certain aspects of the disclosure can be practiced, in
accordance with one or more embodiments;
[0007] FIG. 2 illustrates an example parallel resistive network for
calculating an ambient temperature and an effective heat transfer
coefficient of a device, in accordance with one or more
embodiments;
[0008] FIG. 3 illustrates a device having a parallel resistive
network for calculating an ambient temperature of an environment
and an effective heat transfer coefficient of the device, in
accordance with one or more embodiments;
[0009] FIG. 4 is a flow chart illustrating a method for calculating
an ambient temperature of an environment and an effective heat
transfer coefficient of a device, in accordance with one or more
embodiments; and
[0010] FIG. 5 is a flow chart illustrating a method for determining
and applying at least one modification to a device that corrects
for at least one of (i) an effective heat transfer coefficient of
the device and (ii) at least one environmental heat transfer
condition in the ambient environment, in accordance with one or
more embodiments.
DETAILED DESCRIPTION
[0011] The illustrative embodiments provide a method, a system, and
a computer program product for calculating an ambient temperature
and an effective heat transfer coefficient of an electronic device.
The method includes measuring an internal temperature at a
particular location in the device. The method further includes,
measuring a first temperature at a first location along a first
resistive path of a parallel resistive network and measuring a
second temperature at a second location along a second resistive
path of the parallel resistive network. Based on the internal
temperature, the first temperature, the second temperature, and
pre-established resistive properties of the first and second
resistive paths, an ambient temperature of the device is calculated
independent of any heat generated by the device to the environment.
The method further includes, calculating an effective heat transfer
coefficient of the device that represents a rate at which heat
generated by the device can be dissipated to the ambient
environment in proportion to the temperature difference between the
device and the calculated ambient temperature. The ambient
temperature and the effective heat transfer coefficient are then
provided to a thermal management component of the device.
[0012] The above contains simplifications, generalizations and
omissions of detail and is not intended as a comprehensive
description of the claimed subject matter but, rather, is intended
to provide a brief overview of some of the functionality associated
therewith. Other systems, methods, functionality, features, and
advantages of the claimed subject matter will be or will become
apparent to one with skill in the art upon examination of the
following figures and the remaining detailed written description.
The above as well as additional objectives, features, and
advantages of the present disclosure will become apparent in the
following description.
[0013] In the following detailed description, specific example
embodiments in which the disclosure may be practiced are described
in sufficient detail to enable those skilled in the art to practice
the disclosed embodiments. For example, specific details such as
specific method orders, structures, elements, and connections have
been presented herein. However, it is to be understood that the
specific details presented need not be utilized to practice
embodiments of the present disclosure. It is also to be understood
that other embodiments may be utilized and that logical,
architectural, programmatic, mechanical, electrical and other
changes may be made without departing from general scope of the
disclosure. The following detailed description is, therefore, not
to be taken in a limiting sense, and the scope of the present
disclosure is defined by the appended claims and equivalents
thereof.
[0014] References within the specification to "one embodiment," "an
embodiment," "embodiments", or "one or more embodiments" are
intended to indicate that a particular feature, structure, or
characteristic described in connection with the embodiment is
included in at least one embodiment of the present disclosure. The
appearance of such phrases in various places within the
specification are not necessarily all referring to the same
embodiment, nor are separate or alternative embodiments mutually
exclusive of other embodiments. Further, various features are
described which may be exhibited by some embodiments and not by
others. Similarly, various aspects are described which may be
aspects for some embodiments but not other embodiments.
[0015] The terminology used herein is for the purpose of describing
particular embodiments only and is not intended to be limiting of
the disclosure. As used herein, the singular forms "a", "an", and
"the" are intended to include the plural forms as well, unless the
context clearly indicates otherwise. It will be further understood
that the terms "comprises" and/or "comprising," when used in this
specification, specify the presence of stated features, integers,
steps, operations, elements, and/or components, but do not preclude
the presence or addition of one or more other features, integers,
steps, operations, elements, components, and/or groups thereof.
Moreover, the use of the terms first, second, etc. do not denote
any order or importance, but rather the terms first, second, etc.
are used to distinguish one element from another.
[0016] It is understood that the use of specific component, device
and/or parameter names and/or corresponding acronyms thereof, such
as those of the executing utility, logic, and/or firmware described
herein, are for example only and not meant to imply any limitations
on the described embodiments. The embodiments may thus be described
with different nomenclature and/or terminology utilized to describe
the components, devices, parameters, methods and/or functions
herein, without limitation. References to any specific protocol or
proprietary name in describing one or more elements, features or
concepts of the embodiments are provided solely as examples of one
implementation, and such references do not limit the extension of
the claimed embodiments to embodiments in which different element,
feature, protocol, or concept names are utilized. Thus, each term
utilized herein is to be provided its broadest interpretation given
the context in which that term is utilized.
[0017] Those of ordinary skill in the art will appreciate that the
hardware components and basic configuration depicted in the
following figures may vary. For example, the illustrative
components within device 100 are not intended to be exhaustive, but
rather are representative to highlight components that are utilized
to implement the present disclosure. For example, other
devices/components may be used in addition to, or in place of, the
hardware depicted. The depicted example is not meant to imply
architectural or other limitations with respect to the presently
described embodiments and/or the general disclosure.
[0018] Within the descriptions of the different views of the
figures, the use of the same reference numerals and/or symbols in
different drawings indicates similar or identical items, and
similar elements can be provided similar names and reference
numerals throughout the figure(s). The specific identifiers/names
and reference numerals assigned to the elements are provided solely
to aid in the description and are not meant to imply any
limitations (structural or functional or otherwise) on the
described embodiments.
[0019] With reference now to the figures, and beginning with FIG.
1, there is depicted a block diagram representation of an example
device 100, within which one or more of the described features of
the various embodiments of the disclosure can be implemented. In
one embodiment, device 100 can be any portable electronic device
such as a notebook computer, fitness monitoring device, mobile
phone, watch, smart watch, camera, video recorder, or tablet. In
another embodiment, device 100 may be a generic data processing
system.
[0020] Device 100 includes at least one central processing unit
(CPU) or processor 104. CPU 104 is coupled to system memory 114
and/or non-volatile storage 120, within which firmware 128, thermal
management utility (TMU) 116, and heat transfer utility (HTU) 118
can be stored for execution on CPU 104. According to one aspect,
HTU 118 executes within device 100 to provide logic that performs
the various methods and functions described herein. For simplicity,
HTU 118 is illustrated and described as a stand-alone or separate
software/firmware/logic component, which provides the specific
functions and methods described below. However, in at least one
embodiment, HTU 118 may be a component of, may be combined with, or
may be incorporated within firmware 128 of device 100, or within an
operating system (not pictured) and/or one or more applications
(not pictured).
[0021] Device 100 also includes a TMU 116, which regulates the
operation of CPU 104 and/or one or more input, output, or
input/output components of device 100. In one embodiment, TMU 116
regulates the operation of components of device 100 based on at
least one of a calculated or estimated temperature of an ambient
environment of device 100 and a calculated effective heat transfer
coefficient of device 100. TMU 116 receives both the calculated
ambient temperature of an ambient environment and a calculated
effective heat transfer coefficient of device 100 from CPU 104. In
one embodiment, in response to receiving both of these calculated
values, TMU 116 applies at least one modification to device 100,
such as increasing or decreasing an operating frequency of CPU 104,
adjusting a data input/output rate of wireless radios 140a-n, and
adjusting a brightness of a backlight of display 110. TMU 116 is
illustrated and described as a stand-alone software component.
However, in at least one embodiment, the functionality of TMU 116
may be provided as a component of, may be combined with, or may be
incorporated within firmware 128, HTU 118, or within an operating
system (not pictured) and/or one or more applications (not
pictured). In another embodiment, TMU 116 may execute on a
dedicated processing unit separate from processor 104.
[0022] In one embodiment, TMU 116 may determine when a device 100
is not optimized for an ambient environment. TMU 116 may then
independently determine and apply at least one modification to
components of device 100 that corrects for at least one of (i) the
effective heat transfer coefficient of device 100 and (ii) at least
one environmental heat transfer condition in the ambient
environment. In another embodiment, the at least one modification
is determined by HTU 118, and TMU 116 receives instructions from
CPU 104 that indicate at least one modification to apply to
components of device 100.
[0023] As shown, device 100 comprises several input devices and
output devices for enabling a user to interface with device 100. In
the illustrated embodiment, device 100 includes a camera sensor
142, hardware buttons 106a-"n", microphone 108, and speaker 144.
Microphone 108 may be used to receive spoken input/commands from a
user, and/or ambient sound. Speaker 144 is used to output audio.
Hardware buttons 106a-n are selectable buttons which are used to
receive manual/tactile input from a user to control specific
operations of device 100 and/or of applications executing thereon.
In one embodiment, hardware buttons 106a-n may also include or be
connected to one or more sensors (e.g. a fingerprint scanner)
and/or be pressure sensitive. Hardware buttons 106a-n may also be
directly associated with one or more functions of the GUI and/or
functions of an OS, application, or hardware of device 100. In one
embodiment, hardware buttons 106a-n may include a keyboard.
[0024] Device 100 also includes serial port 132 (e.g. a micro-USB
(universal serial bus) port) which can be one of an input port, an
output port, and an input/output port. Serial port 132 allows a
direct physical connection to and communication of data with a
second device. In one embodiment, serial port 132 may also connect
to a power charger (not pictured) for charging a battery (not
pictured) of device 100.
[0025] Device 100 also includes a display 110, which is capable of
displaying a graphical user interface (GUI) of firmware and/or one
or more applications executing on device 100. In one embodiment,
display 110 is a touch screen that is also capable of receiving
touch input from a user of device 100 interfacing with a displayed
GUI. A GUI displayed by device 100 on display 110 may be rendered
by CPU 104 and/or optionally by a graphical processing unit (GPU),
if present.
[0026] Device 100 also includes one or more wireless radios 140a-n
and one or more antenna(s) 148a-n that enable device 100 to
wirelessly connect to, and transmit and receive data with, one or
more other devices, such as devices 152a-n and server 154. As a
wireless device, device 100 can transmit the data over a wireless
network 150 (e.g., a Wi-Fi network, cellular network, Bluetooth
network, or personal area network).
[0027] Device 100 also includes sensors 112a-n. As described in
greater detail below, sensors 112a-n include at least a first
thermal sensor at a first location (T1) along a first resistive
path of a parallel resistive network, a second thermal sensor at a
second location (T2) along a second resistive path of a parallel
resistive network, and an internal thermal sensor at an internal
location (TO) inside device 100. Thermal sensors may include any
device for measuring a temperature of an environment, including
analog temperature sensors, digital temperature sensors, and/or
thermocouples. In another embodiment, sensors 112a-n may further
include a surface temperature sensor for measuring a temperature of
a surface of device 100. Sensors 112a-n can also include one or
more of infrared (IR) sensors, ambient light sensors, proximity
sensors, global positioning satellite (GPS) sensors, and sensors
used for detecting motion, including, but not limited to,
gyroscopic sensors, accelerometers, and magnetometers. In one
embodiment, one or more sensors of device 100 may be incorporated
within another component of device 100, such as CPU 104.
[0028] FIG. 2 illustrates an example parallel resistive network 200
for calculating an ambient temperature and an effective heat
transfer coefficient of device 100, in accordance with one or more
embodiments. Parallel resistive network 200 comprises first
resistive path 204 and second resistive path 214, which is separate
from first resistive path 204. First resistive path 204 and second
resistive path 214 both physically extend from internal location T0
202 of device 100 to ambient environment 220. Location T0 202 is a
particular location within device 100, such as a designated
location on a printed circuit board. In one embodiment, location T0
202 is a location inside device 100 that is adjacent to a
particular component of device 100 that generates heat, such as CPU
104. In another embodiment, location T0 202 may be a central
location inside device 100.
[0029] First resistive path 204, comprises a first series path from
location T0 202 to ambient environment 220. Along first resistive
path 204, location T0 202 and location T1 208 are coupled via first
resistive material R1 206. Second resistive path 214 comprises a
second series path from location T0 202 to ambient environment 220.
Along second resistive path 214, location T0 202 and location T1
208 are coupled via second resistive material R2 216. In one
embodiment, one or both of T1 208 and T2 218 may be further
separated from ambient environment 220 by a conductive material of
device 100 that has a high conductivity and a very low electrical
resistance value. As described in greater detail in FIG. 3 below, a
first thermal sensor is coupled to location T0 202, a second
thermal sensor is coupled to location T1 208, and a third thermal
sensor is coupled to T2 218.
[0030] In one embodiment, ambient environment 220 is a gaseous
environment, such as air. However, it should be noted that in one
or more embodiments, device 100 may be submerged in a liquid and
ambient environment 220 may be a liquid environment such as salt
water, fresh water, or any other aqueous solution. In yet another
embodiment, the ambient environment may include one or more objects
that are heating or cooling the ambient environment (e.g.,
radiative body heat or a ceiling fan).
[0031] FIG. 3 illustrates device 100 having parallel resistive
network 200 for calculating an effective heat transfer coefficient
312 of device 100 and an ambient temperature (Ta 322) of ambient
environment 220 independent of any heat generated by device 100 to
ambient environment 220, in accordance with one or more
embodiments. As shown, first resistive path 204 and second
resistive path 214 are separated by insulating material 308, which
has a very large resistance. CPU 104 is connected to: (1) internal
thermal sensor 302 at location T0 202; (2) first thermal sensor 304
at location T1 208; and (3) second thermal sensor 306 at location
T2 218. It should be noted that in one or more embodiments,
internal thermal sensor 302, first thermal sensor 304, and second
thermal sensor 306 may be turned for a same or different
temperature ranges. In one example, each of internal thermal sensor
302, first thermal sensor 304, and second thermal sensor 306 is
tuned to measure temperatures in the range of 0-120.degree. Celsius
(C.). In another example, internal thermal sensor 302 is tuned to
measure temperatures between the ranges of 10-100.degree. C. and
first thermal sensor 304 and second thermal sensor 306 are tuned to
measure temperatures in the range of 0-50.degree. C.
[0032] Device 100 may store, within system memory 114, electrical
resistance values 310. Electrical resistance values 310 include
known electrical resistance values and/or conductivity
characteristics for first resistive material R1 206 and second
resistive material R2 216. In another embodiment, electrical
resistance values 310 may also include electrical resistance values
and/or conductivity characteristics for insulating material 308
and/or any conductive material(s) that separate location T1 208
and/or T2 218 from ambient environment 220. While, electrical
resistance values 310 are illustrated as being stored within system
memory 114, in another embodiment, electrical resistance values 310
may be stored within another storage of device 100, such as
non-volatile storage 120.
[0033] By measuring the temperatures at locations T0 202, T1 208,
and T2 218 of parallel resistive network 200, device 100 may
calculate, via HTU 118, the ambient temperature (Ta 322) of ambient
environment 220 and effective heat transfer coefficient (1/Ra) 312
of device 100. Effective heat transfer coefficient 312 represents a
rate at which heat generated by device 100 can be dissipated to
ambient environment 220 in proportion to the temperature difference
between the internal temperature of device 100 and Ta 322. To
calculate Ta 322 and effective heat transfer coefficient 312,
device 100 measures: (1) the internal temperature of device 100 at
location T0 202 via internal temperatures sensor 302; (2) a first
temperature at location T1 208 via first thermal sensor 304; and
(3) a second temperature at location T2 218 via second thermal
sensor 306. Once the temperatures at each of locations T0 202, T1
208, and T2 218 have been measured, device 100 may calculate
effective heat transfer coefficient 312 and Ta 322, via HTU 118, by
solving the following equations:
(T2-T0)/R2=(Ta-T2)/Ra
(T1-T0)/R1=(Ta-T1)/Ra
[0034] At the time of calculation, Ta (Ta 322) and Ra (Ra 320),
which is the ambient convective resistance of ambient environment
220, are unknown. In one embodiment, HTU 118 simultaneously
calculates the above system of equations using matrices. In another
embodiment, the above equations may be sequentially calculated by
first solving for either Ta 322 or Ra 320 in a first of the two
equations and inserting the result into the second of the two
equations above. By solving the equations, HTU 118 learns effective
heat transfer coefficient 312 of device 100 and Ta 322 of ambient
environment 220. In response to calculating effective heat transfer
coefficient 312, HTU 118 provides effective heat transfer
coefficient 312 and Ta 322 to TMC 316. In one embodiment, TMC 316
includes a processing device that executes TMU 116. As described in
FIG. 2 above, if present, any conductive materials separating one
or both of T1 208 and T2 218 from ambient environment 220 have a
high conductivity and a very low electrical resistance value. Due
to the high electrical conductivity and low electrical resistance
of these conductive materials, the conductive materials, if
present, have a negligible effect on the effective heat transfer
coefficient 312 and Ta 322 and may be omitted from the above
calculations.
[0035] In response to receiving effective heat transfer coefficient
312 and Ta 322, TMC 316 determines whether a current operating mode
of device 100 is optimized for the ambient environment 220. As
utilized herein, an operating mode refers to the
configuration/operating characteristics of one or more components
of device 100. For example, an operating mode may include
configuration parameters for an operating frequency of CPU 104, an
input/output data rate of wireless radios 140a-n, and a brightness
of a backlight of display 110. An enhanced operating mode regulates
the performance of one or more components of device 100 based on Ta
322 and the effective heat transfer coefficient 312. For example,
an enhanced operating mode may set a maximum, minimum, or current
operating frequency of CPU 104 and/or an input/output data rate of
wireless radios 140a-n to a particular level. In one embodiment,
the particular level is determined as a specific operating
frequency and/or an input/output data rate which: (1) maximizes the
performance of the device; (2) maintains a maximum surface
temperature of device 100 below a pre-established maximum surface
temperature threshold; and/or (3) maintains the internal
temperature of device 100 below a pre-established maximum internal
operating temperature threshold.
[0036] In one embodiment, for a high heat transfer coefficient 312
value (e.g., when a breeze is being applied across a surface of
device 100 and/or device 100 is located in a cool ambient
environment 220), the enhanced operating mode of device 100 may
include an increased performance level of one or more components of
device 100. In another embodiment, for a low heat transfer
coefficient 312 value (e.g., the air is stagnant and/or device 100
is located in a warm ambient environment 220), the enhanced
operating mode of device 100 may include a reduced performance
level of one or more components of device 100. In still another
embodiment, an enhanced operating mode may also maximize the
configuration and/or operating characteristics of one or more
components of device 100 to achieve a desired and/or optimal power
consumption.
[0037] In response to determining the current operating mode of
device 100 is not optimized for ambient environment 220, TMC 316
may calculate an enhanced operating mode for the device in the
ambient environment. The calculated enhanced operating mode
establishes at least one maximum and/or improved operating
specification for at least one component of device 100 that
maintains the internal temperature at location T0 202 below a
pre-established maximum internal operating temperature threshold.
In another embodiment, device 100 may be configured with surface
temperature sensor 314 for measuring the surface temperature at an
outside surface of device 100. Alternatively, in the event device
100 is not configured with surface temperature sensor 314, HTU 118
and/or TMC 316 may estimate a surface temperature of device 100
based on effective heat transfer coefficient 312, Ta 322, and the
measured temperatures at T0 202, T1 208, and T2 218. In still
another embodiment, the at least one maximum and/or improved
operating specification for the at least one component continually
maintains a maximum surface temperature of device 100 and/or an
average surface temperature of device 100 below a pre-established
temperature threshold.
[0038] Based on the calculated enhanced operating mode, TMC 316 may
determine whether at least one modification exists that can be
applied to the at least one component of device 100 that corrects
for at least one of (i) the effective heat transfer coefficient 312
of the device and (ii) at least one environmental heat transfer
condition in the ambient environment. The at least one modification
includes at least one adjustment/change to the at least one
component that modifies the current operating mode of device 100 to
the enhanced operating mode. In one embodiment, the at least one
modification comprises an increase or a decrease to at least one
of: a brightness level of display 110, a maximum and/or current
data rate of wireless radios 140a-n, and a maximum, minimum, and/or
current operating frequency of CPU 104. In another embodiment, the
at least one modification includes an adjustment to a
pre-determined maximum internal operating temperature threshold of
device 100 based on Ta 322 and effective heat transfer coefficient
312.
[0039] In response to determining at least one change exists that
can be applied to the at least one component that changes the
current operating mode of device 100 to the enhanced operating
mode, TMC 316 may apply the at least one change to the at least one
component. For example, in a cold environment, TMC 316 may increase
a current operating frequency of CPU 104 to change the current
operating mode of device 100 to the enhanced operating mode.
[0040] Referring now to FIGS. 4-5, there are illustrated flow
charts of various methods for calculating an effective heat
transfer coefficient of a device, according to one or more
embodiments. Aspects of the methods are described with reference to
the components of FIGS. 1-3. Several of the processes of the
methods provided in FIGS. 4-5 can be implemented by CPU 104
executing software code of HTU 118 within a mobile device or
generic data processing system. For simplicity, the methods
described below are generally described as being performed by
processor execution of HTU 118 and TMC 316 of device 100.
[0041] Referring now to FIG. 4, there is depicted a high-level
flow-chart illustrating a method for calculating an effective heat
transfer coefficient of a device (device 100), in accordance with
one or more embodiments of the present disclosure. Method 400
commences at initiator block 401 then proceeds to block 402. At
block 402, the internal temperature of device 100 is measured. The
method then proceeds to block 404 where a first temperature is
measured at a first location along a first resistive path of a
parallel resistive network. HTU 118 then measures a second
temperature at a second location along a second resistive path of
the parallel resistive network (block 406). At block 408, HTU 118
calculates: (1) the ambient temperature of an ambient environment
of device 100 independent of any heat generated by the device 100
to the ambient environment and (2) the effective heat transfer
coefficient of device 100 based on the internal temperature, the
first temperature, the second temperature, and pre-established
resistive properties of the first resistive path and the second
resistive path, which are located in a storage of device 100. At
block 410, the effective heat transfer coefficient of device 100
and the ambient temperature of the ambient environment are provided
to a thermal management component of device 100. Based on the
ambient environment and the effective heat transfer coefficient, a
thermal management component of device 100 may autonomously
regulate the operation of a CPU and/or one or more input, output,
or input/output components of device 100 in order to optimize
and/or maximize the performance thereof for the rate at which heat
generated by device 100 can be dissipated to the current ambient
environment. The method then terminates at block 412.
[0042] Referring now to FIG. 5, there is depicted a high-level
flow-chart illustrating a method for determining and applying at
least one modification to a device that corrects for at least one
of (i) an effective heat transfer coefficient of the device and
(ii) at least one environmental heat transfer condition in the
ambient environment, in accordance with one or more embodiments of
the present disclosure. Method 500 commences at initiator block
501. At block 502, TMC 316 calculates whether a current operating
mode of device 100 is optimized for ambient environment 220. In
response to determining the current operating mode of device 100 is
optimized for ambient environment 220 (block 504), method 500
terminates at block 514.
[0043] In response to determining the current operating mode of
device 100 is not optimized for ambient environment 220 (block
504), TMC 316 calculates an enhanced operating mode for device 100
(block 506). TMC 316 then determines, at block 508, whether at
least one change can be applied to at least one component of device
100 that will transform the current operating mode of device 100 to
the enhanced operating mode. In response to determining at least
one change exists (block 510), the at least one change is applied
to the at least one component of device 100 (block 512). Method 500
then terminates at block 514. In response to determining no change
exists that can transform the current operating mode of device 100
to the enhanced operating mode (block 510), the method 500
terminates at block 514.
[0044] In the above-described flow charts, one or more of the
method processes may be embodied in a computer readable device
containing computer readable code such that a series of steps are
performed when the computer readable code is executed on a
computing device. In some implementations, certain steps of the
methods are combined, performed simultaneously or in a different
order, or perhaps omitted, without deviating from the scope of the
disclosure. Thus, while the method steps are described and
illustrated in a particular sequence, use of a specific sequence of
steps is not meant to imply any limitations on the disclosure.
Changes may be made with regards to the sequence of steps without
departing from the spirit or scope of the present disclosure. Use
of a particular sequence is therefore, not to be taken in a
limiting sense, and the scope of the present disclosure is defined
only by the appended claims.
[0045] Aspects of the present disclosure are described above with
reference to flowchart illustrations and/or block diagrams of
methods, apparatus (systems) and computer program products
according to embodiments of the disclosure. It will be understood
that each block of the flowchart illustrations and/or block
diagrams, and combinations of blocks in the flowchart illustrations
and/or block diagrams, can be implemented by computer program
instructions. Computer program code for carrying out operations for
aspects of the present disclosure may be written in any combination
of one or more programming languages, including an object oriented
programming language, without limitation. These computer program
instructions may be provided to a processor of a general purpose
computer, special purpose computer, or other programmable data
processing apparatus to produce a machine that performs the method
for implementing the functions/acts specified in the flowchart
and/or block diagram block or blocks. The methods are implemented
when the instructions are executed via the processor of the
computer or other programmable data processing apparatus.
[0046] As will be further appreciated, the processes in embodiments
of the present disclosure may be implemented using any combination
of software, firmware, or hardware. Accordingly, aspects of the
present disclosure may take the form of an entirely hardware
embodiment or an embodiment combining software (including firmware,
resident software, micro-code, etc.) and hardware aspects that may
all generally be referred to herein as a "circuit," "module," or
"system." Furthermore, aspects of the present disclosure may take
the form of a computer program product embodied in one or more
computer readable storage device(s) having computer readable
program code embodied thereon. Any combination of one or more
computer readable storage device(s) may be utilized. The computer
readable storage device may be, for example, but not limited to, an
electronic, magnetic, optical, electromagnetic, infrared, or
semiconductor system, apparatus, or device, or any suitable
combination of the foregoing. More specific examples (a
non-exhaustive list) of the computer readable storage device would
include the following: an electrical connection having one or more
wires, a portable computer diskette, a hard disk, a random access
memory (RAM), a read-only memory (ROM), an erasable programmable
read-only memory (EPROM or Flash memory), an optical fiber, a
portable compact disc read-only memory (CD-ROM), an optical storage
device, a magnetic storage device, or any suitable combination of
the foregoing. In the context of this document, a computer readable
storage device may be any tangible medium that can contain, or
store a program for use by or in connection with an instruction
execution system, apparatus, or device.
[0047] While the disclosure has been described with reference to
example embodiments, it will be understood by those skilled in the
art that various changes may be made and equivalents may be
substituted for elements thereof without departing from the scope
of the disclosure. In addition, many modifications may be made to
adapt a particular system, device, or component thereof to the
teachings of the disclosure without departing from the scope
thereof. Therefore, it is intended that the disclosure not be
limited to the particular embodiments disclosed for carrying out
this disclosure, but that the disclosure will include all
embodiments falling within the scope of the appended claims.
[0048] The description of the present disclosure has been presented
for purposes of illustration and description, but is not intended
to be exhaustive or limited to the disclosure in the form
disclosed. Many modifications and variations will be apparent to
those of ordinary skill in the art without departing from the scope
of the disclosure. The described embodiments were chosen and
described in order to best explain the principles of the disclosure
and the practical application, and to enable others of ordinary
skill in the art to understand the disclosure for various
embodiments with various modifications as are suited to the
particular use contemplated.
* * * * *